It is said that Rolex watches practice evolution, rather than revolution. With very strong, but classic visual identities, the look of Rolex watches have rarely been changed drastically; one has to develop a keen eye, and some technical knowledge, to know the difference between models.
Such is the case with the GMT-Master and GMT-Master II. With a timeless design right from the start, all it needed were technological upgrades over the decades.
Here’s what sets the two watches apart.
The Beginnings of the GMT-Master
The history of the GMT-Master is pretty well known. In the 1950s, long-haul and transatlantic flights became possible and more commonplace. This development made the world smaller, but presented a problem for pilots – jetlag. Not knowing the timezone back home, and staying in a place hours behind or ahead, wreaked havoc on their circadian rhythms.
from left: Rolex GMT-Master Blue Red Pepsi Bezel ref 1675, and Rolex GMT-Master II Pepsi Bezel Jubilee Steel Watch ref 126710.
Pan American Airways thought that the solution was a watch that displayed two timezones at once, so that pilots can monitor their home timezone, while also knowing the time in their destination. They commissioned Rolex for the task, and in 1954, the Rolex GMT-Master was launched.
The Rolex GMT-Master came with a 24-hour hand, and 24-hour marked bezel to display a second timezone, along with the traditional hour and minute hands to display the home timezone.
Rolex GMT-Master and GMT-Master II Over the Years
Since 1954, there have been many iterations of the GMT-Master and GMT-Master II. Each line has four generations to-date.
GMT-Master (1954 – 1999) : 6542, 1675/x, 1675x and 16700
GMT-Master II (1982 – present) : 16760, 16710 and two current models – 11671x and 12671x.
The GMT-Master II eventually replaced the GMT-Master in 1999, but there were a few years of overlap between the two models as shown above.
The Rolex GMT-Master is available in a bevy of bezel colors. Seen here: black bezel, black-red bezel (Coke) and blue-red bezel (Pepsi).
Rolex GMT-Master and GMT-Master II: What’s the Difference?
Why was there a need for a second edition GMT-Master, if the appearance of the watches did not change?
The main difference is in the functionality of the watches. As explained earlier, the GMT-Master can display time in two time zones. The GMT-Master II meanwhile, can display three separate timezones. Rolex was able to do this by making the 24-hour hand (the hand with an arrow) independent from the hour and minute hands.
While the center hour and minute hands tell home time, the 24-hour hand can be moved freely on the dial and read with the 24-hour bezel to show another time zone. Rotating the bezel in either direction allows for the reading of a third time zone.
The movement for the latest Rolex GMT-Master II watches, Caliber 3285, uses the Chronergy escapement, and is regulated to just +2/-2 seconds per day.
This feature of the GMT-Master II called for an updated movement, and in order to accommodate it within the watch, the GMT-Master II also had to be thicker. This is the only real visible difference between the two watches, aside from very minor tweaks over the years.
The main appeal of the GMT-Master is in its bezel, and the materials used for it have also changed over the years.
Bakelite – very early models made use of Bakelite, a plastic made from synthetic components. These were prone to cracking, so Rolex changed the material to aluminum beginning 1956.
Aluminum – while these are more durable than the Bakelite bezels, the luminous radium numerals on the Bakelite bezels weren’t possible on them, which altered the overall appearance of the GMT-Master.
Cerachrom, Rolex’s patented ceramic material, has been used for GMT-Master II bezels since 2007.
Cerachrom – beginning 2007, Rolex began fitting the GMT-Master II with their patented Cerachrom bezels. Made from extremely hard ceramic material, the Cerachrom is virtually scratch-proof, and fade-proof.
With a 65-year history, the GMT-Master II remains one of the most popular watches of Rolex. Its classic looks and practical function ensures that it will still be around for decades to come.